Ridged Stripes for Back and Sleeves.
Row 1 (rs): With A, knit.
Row 2: With A, purl.
Rows 3 and 4: With B, k4, *sl 2, k4, rep from * to end.
Rows 5 and 6: Rep Rows 1 and 2.
Rows 7 and 8: With C, k1, sl 2, *k4, sl 2, rep from * to last st, k1.
Rows 9-14: Repeat Rows 1-6.
Rows 15 and 16: With D, repeapt Rows 7 and 8.
Start out with Color A (CA) and do the cast on and the ribbing and the row of knit and purl (rows 1&2 of the pattern). Then just leave the CA there at the edge and leaving a tail of Color B (CB) just start knitting with it.
Rows 3 and 4: With B, k4, *sl 2, k4, rep from * to end.
Knit 4 with CB then slip 2 purl wise, and k4. Keep slipping 2 and knitting 4 all the way across after the first K4. You will be getting 4 stitches of the CB on your right hand needle (RHN) followed by 2 of CA, all the way across, ending with 4 of CB. You will just be working with the one color all the way across and you keep all of the ‘floats’ on the back of the piece (the purl side). That is row 3.
Row 4 is done the same way, but it is a little different.
The pattern doesn’t say to bring the yarn to the front to slip the 2 each time, but if you don’t bring the working yarn to the front and out of the way it will make a little strand of yarn going across the 2 stitches of CA in the front. It could be that that is what they want. Does the picture show clean lines of CB going across a background of CA, kind of like a line of hyphens - - - -? Or is there a little strand of yarn connecting all the hyphens to each other? I suspect it is the first choice. I think it looks better anyway.
To get that you need to bring the yarn to the front between the needles as if you were preparing to purl, then slip the 2 stitches of CA purl wise, then move the yarn to the back between the needle tips so you can knit the next 4 stitches. You will be working with the back side facing you and you will immediately see the little strand get carried across the side facing you (where all the others are) and if you turn the work over so the right side is facing you there are no floats (or strands) on that side.
For rows 5 and 6 (repeat rows 1 & 2) you are back where you can access the CA again and you do those two rows with CA because it doesn’t tell you to use any other color.
Rows 7 & 8 introduce Color C (CC) just leave a tail of it and start knitting. These two rows produce the same hyphens as rows 3 & 4 did, but they are off set between the others. Again on row 8 you will need to bring the yarn forward for the clean hyphens, then back again to knit so that all the floats end up on the back.
Rows 9-14 repeat rows 1-6 so you will use the colors given there. Rows 15-16 repeat rows 7 and 8 but with Color D. So you end up with one background color (CA) and hyphens of the other colors. You will never need to cut the CA, but if the others need to be carried too far up the side you will want to cut them and reintroduce them as needed. If you do that just leave a tail where ever you introduce a yarn and start knitting with it.
This kind of color work is a little like stranded knitting (or is a type of stranded knitting), when you slip the 2 stitches each time and then knit the first of the next 4 you want to make sure the little bit of strand of your working yarn that is being carried across the gap doesn’t get too short. You could accomplish this by stretching the work a little after you do the first of each group of 4 stitches.